#646FA1
Closest named color: Dull Blue (#49759C). oklch(55.3% 0.079 274), rgb(100, 111, 161).
Aa
White text reads best on this color (4.84:1).
About this color
#646FA1 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.079 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Dull Blue (#49759C), ΔE 0.038 away. White text reads best on it, at 4.84:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.079) |
| Temperature | cool |
| Nearest name | Dull Blue (#49759C) |
| Black text | 4.33:1 |
| White text | 4.84:1 |
Values
| HEX | #646FA1 |
| RGB | rgb(100, 111, 161) |
| HSL | hsl(229, 24%, 51%) |
| OKLCH | oklch(55.3% 0.079 274) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #646FA1 | 4.84:1 | AA | Lc -79.0 | Fine for body text |
| Black text on #646FA1 | 4.33:1 | AA large text | Lc 30.5 | Non-text elements, placeholder text |
| #646FA1 text on white | 4.84:1 | AA | Lc 73.6 | Content text, not long reading |
| #646FA1 text on black | 4.33:1 | AA large text | Lc -28.1 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 600.
-
Step 50
50
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E7E9F1
oklch(93.5% 0.011 274.9)
-
Step 200
200
#D5D8E7
oklch(88.4% 0.021 276.9)
-
Step 300
300
#B9BFD8
oklch(80.8% 0.036 274.9)
-
Step 400
400
#959FC5
oklch(70.8% 0.057 273.4)
-
Step 500
500
#7B87B6
oklch(63.2% 0.072 273.1)
-
Step 600
600 (this color)
#646FA1
oklch(55.3% 0.079 274)
-
Step 700
700
#545D8B
oklch(49.1% 0.075 274.9)
-
Step 800
800
#444C71
oklch(42.6% 0.062 274.1)
-
Step 900
900
#3A405B
oklch(37.8% 0.047 274.3)
-
Step 950
950
#222535
oklch(26.9% 0.03 276)
#646FA1 with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #5F74A3 | 0.014 |
| Deuteranopia (no green cones) | #5A6FA0 | 0.014 |
| Tritanopia (no blue cones) | #527981 | 0.071 |
| Achromatopsia (no color) | #717171 | 0.079 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646FA1
#646FA1
oklch(55.3% 0.079 274)
- #827239
#827239
oklch(55.4% 0.079 94)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #646FA1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dull Blue #49759C ΔE 0.038
- Stormy Blue #507B9C ΔE 0.043
- Metallic Blue #4F738E ΔE 0.045
- Flat Blue #3C73A8 ΔE 0.046
- French Blue #436BAD ΔE 0.048
- Muted Blue #3B719F ΔE 0.048
- Cerulean #457B9D ΔE 0.049
- Dark Lavender #856798 ΔE 0.053
Use #646FA1 in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.